1. Enzymes I.N. Headings Vocabulary Important Words

2. Chemical reactions and Enzymes
Change from one set of chemicals to another set of chemicals
Involves the breaking of bonds & the formation of new bonds
Activation energy:
Energy needed to get a reaction started

3. What is an ENZYME?
An enzyme is a special type of protein called a catalyst
Catalyst: substance that speeds up rxn b/c it lowers the activation energy (AE)
cells use enzymes to speed up reactions
Very specific: usually only catalyzes one item called the SUBSTRATE

4. HOW DOES AN ENZYME WORK?
Enzyme comes in contact with substrate at certain spot called ACTIVE SITE
Fits together like a “lock & key”
Bonding at active site weakens the bonds in the substrate
Makes it easier to change substrate

5. What are enzymes used for? What regulates them?
Used for digestion, photosynthesis, & DNA reproduction
Regulated by:
changes in Ph
temperature
other proteins, and chemicals

6. Check for Understanding!!!
Enzymes are a form of ___.
a. carbohydrate b. lipid c. protein
Enzymes can speed up a reaction, so they are called ___.
a. catalysts b. reactants c. inhibitors
The area where the enzyme attaches to the substrate is called the ___.
a. active site b. cohesion area c. vectors
4. If the enzyme is heated, it will change shape. This ___ not affect the ability of the enzyme to work.
a. will b. will not
Enzymes work because they lower the ___.
a. chemical reactant rate b. active site location
c. activation energy